Up until now, there has been proposed a portable wireless device capable of being folded exemplified by a foldable wireless cellular phone, the portable wireless device comprising an upper case, a lower case and a hinge portion rotatably connecting the upper case and the lower case to ensure the upper and the lower cases being in one of a state to be opened (hereinafter simply referred to as an opened state) and a state to be closed (hereinafter simply referred to as a closed state). This results in the fact that the portable wireless device has two advantages, one of which is user-friendliness in that it has a wide display to be watched in the opened state, while another of which is portability in that the portable wireless device has compact shape in the closed state.
In recent years, the wireless cellular phone is expected to be smaller and thinner than it used to be. The conventional portable wireless device capable of being folded comprises an upper case to have an antenna element accommodated therein, a lower case to have a feeding circuit accommodated therein, and a hinge portion having a feeder line to have an electric power supplied therethrough to ensure that the electric power is supplied from the feeding circuit to the antenna element, which is disclosed in patent document 1.
Additionally, in recent years, an antenna characteristic with the portable wireless device being placed on a desk with the fold closed, that is to say, “a stand-by mode” is regarded as an important feature. The conventional portable wireless device capable of being folded comprises a terminal accommodating a circuit board having a front surface (a first surface) and a back surface (a second surface) to respectively have antenna elements mounted thereon, which is disclosed in patent document 2. The conventional portable wireless device is operative to maintain telecommunication quality by utilizing the antenna element mounted on the second surface under the condition that the antenna characteristic of the antenna element mounted on the first surface is deteriorated caused by the desk and the antenna element being closely positioned with each other.
(patent document 1)
Japanese Patent Laying-Open Publication No. 2001-156898
(patent document 2)
Japanese Patent Laying-Open Publication No. 2002-368850